1. Field of the Invention
The subject invention relates to a fuel tank assembly, and more particularly, to a mechanically sealed joint used to connect a filler pipe to a fuel storage tank.
2. Description of the Related Art
A common method of providing a seal at the filler neck joint is to extend the neck of the filler pipe through an opening in the fuel tank and solder the adjoining material of the two components to form an assembly. Generally a lead-tin material is used to solder the joint. The filler neck may be provided with a lead-tin coating or the like to obtain a secure solder joint and provide corrosion resistance.
With soldered construction, a clean metal surface on the tank and filler neck must be provided at the joint. The tank generally has a corrosion resistant coating on the base metal that may have to be removed in the area to be soldered. A problem with removing the coating is that the corrosion resistance aspect is defeated by exposing the base metal. Therefore, a re-application of additional corrosive resistant material may be required to obtain an acceptable corrosion free life expectancy from the assembly. Obviously, this method is also limited to metallic fuel tanks.
Another method of connecting a filler pipe to a fuel tank involves the use of a resilient grommet. In this type of assembly the grommet is inserted into an opening in the fuel tank and then the filler neck is clamped or fastened to the grommet. The resiliency of the grommet allows it to deform and may permit movement of the filler pipe relative to the tank. This technique is applicable to both metallic and polymeric fuel tanks.
Yet another common technique is the use of an intermediary elastomeric hose that connects at one end to the main fuel filler tube and at the other end to a fuel tank nipple or xe2x80x9cspudxe2x80x9d connector.
Although these grommet and hose techniques provide leak tight seals, they do not prevent the permeation of fuel vapors at the assembly. Recent P-ZEV legislation restricts the amount of fuel vapor that can be released from the fuel tank, therefore, a more permeation-resistant assembly technique is needed.
The present invention addresses the need for a more versatile and permeation-resistant joint in the construction of fuel filler neck assemblies. A leak tight seal is provided that eliminates the need to use solder and solder compatible coatings yet provides a durable connection with good resistance to separation or leak formation.
According to one aspect of the invention there is provided a filler neck assembly for interconnecting a fuel filler tube to a fuel tank. The filler neck assembly comprises a fuel filler tube for providing fluid passage to the fuel tank and a fuel spud connector adapted to be fixedly secured to the fuel tank. The spud connector has an inner wall defining a fluid passageway into the fuel tank and an open distal end for receiving the fuel filler tube. A resilient seal is interposed between the inner wall of the spud connector and the fuel filler tube for sealing the connection therebetween of fuel vapor.